Strain insulator



w. T. GonuARD. STRMN INSULATDR. APPLICATION FILED APRMI. 1916.

4, 1 2 sainssneerV Patented Feb.1 922.

his Arto/mm W. T. GODDARD. STRAIN INSULATOR. APPLICATION FILED mm, 191s.

1 ,406, 953 Patented Feb. 14, 1922.

2 SHEETS-SHEET 2- WIT NESSS: IN1/EAI T00 mm H, PP y Waefwqdmz Mmm/nv 14 FCZ/Q4 his Arrofmfrs Y 'an eilicient combination 'and tween the insulating'4 and WALTER T. GCDDABD, OF HAMILTON.

ASSIGNMENTS, T0 LOCKE INSULAT ONTARIO, CANADA, AssIGNon, BY MESNE oa conroaATIoN, or BALTIMORE, MARY- LAND, A CORPORATION OF MARYLAND.

sraarn INSULATOR.

Spccicaton of Letters Patent.

Patented- Feb. 14, 1922.

' Application filed April 4, 1916. Serial No. 88,814.

To all whom it mycomem:

Be it known thatI, WALTER T. GODDARD, of Hamilton, Province of Ontario and Dominion of Canada, have invented certain new and useful Improvements in Strain lnsulators; and l do hereby declare the followin to be a full, clear, and'exact description o the saine, ref erence being had to the accompanying drawings, forming a partof thisspecification, and to the reference-numerals marked thereon.

My invention relates to strain insulators of the general character employed for supporting high tension' conductors, and embodying, in a broad aspect, a pair of inetallic strain or tension members connected by one or more insulating sections or meinbers, and it has for its'lpurpose' to provide arrangement of parts possessing the 'necessary strength to withstand theheavy'strains of 'a high tension line. A furtherv purpose of the structure is to alord such a mechanical union bestrain members of each'unit as to entirely'obviate any destructive action upon the insulating member that -'would otherwise result rom'a difference between itscoe'icient-of expansion and that of the strainmembei". An additional object of the invention is in providing a device which 'can be'readily assembled andeconomically 'made, rendering it; entirely practicable,

while'at the same'timepossessing all the re- 4sulators,

q uirements Iof insul tors' of'the type mentioned. To these and Vother ends the invention Aconsistsv in` certain iniprove'iments, and

'1 combinations of parts, all as will be hereinafter'more fully described; the novel features being pointed out-in the claims at the Aend of the specificatitin'.y`

In-the drawings: Fi e 1 is a sectional view showing the application of my improvements to an insulator of usual type, with the metal cap or upper strain member in the position in upon the insulating memtoits attachment thereto;

b'er preliminarily vFigureQ is a similar View with the parts completely assembled;

Figure 3 is a horizontal sectional view on line 3*-3 of Figure 2;

Figure 4 is a side elevation of the coin- 'pleted structure;

Figure 5 is a sectional view showing the manner ofassembling the parts which unite or lock the inner strain member within the hollow portion of the insulator member;

Figure 6 is a similar view showing a fui'- ther step in the operation;

Figure 7 is a view in elevation showing the form of locking member or plate employed as 4part of the retaining means for locking a strain member within thehollow portion ofthe insulator, and

Figure 8 is a sectional view of a modification.

Similar reference numerals in the several figures indicate the same parts.

ln the construction of insulators oi thc general character already referred to, the more or less general practice has been to obtain a tightun-ion between the insulator and lstrain members'by cementing them together,

but there has been considerable objection to this method owing to the fact that the strain member is usually formed of metal While the insulator member is= of porcelain or similar material. The difference in the coefficients-of expansion of the metal and insulating substance causes 'the latter to readily crack and break under changes of atmospheric conditions, and an additional disadvantage is found in the fact that dehydration of the cement binder takes place after the insulator has been in actual use for a time, causing deterioration of the insulators, and a lessening of its efficiency. Strain inwhen in actual operation, are subjected to enormous loads, and it has been a difficult matter to so connect the metal cap or strain member, which is arranged upon the upper portion of the insulating member one point or anot eig-under certain strains, which is due to the localizing o the strain at one point of the insulatingmember, and this is overcome in my invention by distributing the load, or in other words', e ualizin it around the different portions o the insu ating member.

The improvements, which are now to-be described more particularly, may be carried out in a variety of ways one of which is illusstrated in the drawings, by way of example and includes an insulating member of the usual type formed of porcelain oi' similar non-conducting material, and including a top portion l and a skirt 2, while an annumembers 19, each angular or inclined 6 0 lar groove or recess 3 is arranged at the base of thev top portion for a purppse that will presentlyappear.v Cooperating with the top portion 1 is a metal cap, carrying a lugfl which is provided with the usualeye` or opening 5 by which the structiire: may: be

connected to the cooperating strain menbr fvtheagljacent insulatin formed to provide'a-plurality of yielde'blc and unit. The cap-is independently movable retainingportions or sections which are brought into locking eu- .gag'enient with the -ins'ulating .inember, and in the present arrangement,-.theicap -is split on a series of lines -6 from its lower edge. upwardly, forming a series of yieldable 'spring arms or sections7, each of Whiclrcarries an nwardb7 projecting..l alnge or enlangement 8 that engages the groove ongthe insulating separation under atmospheric changes or other conditions that would require such acv tion, to" prevent vbreaking the insulating memben The plates 19 are formed from blanks, as'shown in Figure 7, and each pro- .,iided ,ivith a series of slots or openings 2U extending radially from the periphery. The outer portion of the plate is bent inwardly, as shown at 21, in Figure 5, to reduce the diametei',suiiiciently to permit the plate to be inserted through the openingl or hollow portionV 14.-. In assembling the parts, the locking plates are positioned over the post 17, one `iat a time,.ea ch=being provided with-.a central opening .22 that engages the said post. A ,-1 plunger lor stamping member4 2 3 4is then brought intoiengagement with 4:the outer surace of-theplate to forcethe latter inwardly member. In-theassemblingmthe cap upon, until it assumes a .niofe llattened'position,

thel insulating membemthe section 7 initially assumes the-posit-ion-shovvnin Figure .1, and mniyfbe forced,` yinwardlyin diilerent'ways, as for instance, by employing a compression ring or rband 9,avl1ich may 'be forceddown over the cap until yit.engages -tlie outwardly projecting flange 10: at :the {loi'ver edgelthere-V of. This compressesfor moves inwardly Athe yieldable sections of thecap .until ,they-1assuine the position shoWnfin-'Figure 2 withV the lugs 48 engaged. Thejband 9 is retained 1n its lowermost position by.` any,.desir,able

means', as-for instance, Vloekingpins 11, and

12 is a compression washer arranged 4in the groove -3 vand against Awhich the enlargements 8 are engaged. A -compressionwasher 13 may also ,be employed between .the upper portion ofthe cap and-the upperportion of the insulator ,member, althoughtliis is not an' essential part of! the invention.

The insulator member is provided with the usual interior hollow portion 14 which;

is provided with a flange or shoulder 15 that is preferably inclined at an angle ol 45 or less with respect to a plane at right angles to the normal direction of strain, .the object ofwhieh arrangement will be more apparent presently. f

The shoulder 15 affords a means `for engaging and locking the strain member which cooperates with the interior ofthe insulator member, and which in the present embodiment includes 4a support consisting of a sleeve 16 having threaded engagement with a pin o r-post 17, the innerend of-which car ries the retaining-means embodying a head 18 against which are laminations in the form of platesor locking portion that cooperates with the inclined shoulder 15, as shown in Figure 1. Owingto the angle of the shoulder 15, the retaining means 4is prevented from wedging or freezing againstit, bv reason of strains exerted between the parts, and the parts are always tree for slight4 secured a series ofbeing provided with an- .and the inclined portionlQ is forced over the .shoulder 18 ofgthe insulating member. When the several laminated plates are inftheir completely' assembled positions, they :appear as sho-wn in Figure -6,.afi`ording a plurality of Elaminatedinclined or angular portions extending parallel to and, supported on the shoulder l5, and maintain the strain meniyber seeurelymfithimthe insulating member so that ,the parts cannot loe separated ,except by breaking or destroyingone of them. After tlleretainin ymeans is properly positioned onthepost l thesleeve 16 is then threaded .thereonfthe Vlatter being open at its outer I. end-top errnit of inserting a tool for engagement Witlnthe; slot 24,l to elect rotation of the post ...with -relatiion to 4the sleeve.. The latter is held against' movement relatively to theinsulating member byA means of a .projeetion or` Alug t25 engaging a cooperating re- 4t.cess 26;.upon the -iusulatingmemben The sleeve -16 andfpost 17 are in lspaced relation to ,thewalls of the insulating member, permitting expansion and contraction` of the metalwitheut distorting the porcelain and in order to .prevent relative latepalimovrement of said parts, 4I employ a .washer or spacingf member I27, which islpreferably of U-shaped formation in cross section .and restsupon a shoulder .-28 ofthe-,sleeve 16 to prevent its outward movement, while 29 is a shoulder formed on the insulating member and cooperating with the inneredge of said spacing deyicesoi as to .hold .the latter .against ...movementinwardly of its normal position, as shown clearly in Figure 2. 30 designates a compression plate or washer which may b e employedbetween the insulating member and the. inner face of the head. or enlarge ment/18 on the post 17. In order to lock the post 17 against rotation withrelation to the sleeve 1 6, the end s ofthe post 17, which define the slot 24, may be bent outwardly, as indicated at 31 in 'Figure 2, by the insertion of a suitable instrument Within the slot 211. 32 are openings or eyes formed inthe outer end of the sleeve 16, and by which the strain member may be attached to the cap of the adjacent insulating unit.

In Figure 8, I have shown a modified form or" construction, embodying a hollow support or tube 33, with an enlargement 34 at its inner end for engagement with the shoulder 35. The enlargement 34 is formed on the tube after the latter is positioned Within the insulator, by exertin sufficient fluid pressure within the tube an in such manner as to expand its outer end over the shoulder, thus holding the support engaged with the insulator. The outer ends of the tube 33 may then 1be pressed together to rovide a connecting portion 36, having t e opening 37 y therein. The tube is preferably filled with cement, or other analogoussubstanoe, after forming the enlargement at the inner end, in order to aii'ord a solid connection, and to withstand the necessary strains.

- I claim as my inventlon:

1. In a strain insulator, the combination with an insulating member-having an angularly arranged interior shoulder, the angle of the said shoulder with reference to a plane at right angles to the normal direction of strain being not greater than forty-five degrees, of a strain member extending interiorly of the insulating member and including a shouldered support, and retaining means for said support, saidy means including a plurality of cup shaped plates adapted to fit between the respectlve shoulders formed on the insulating member and the said support.

2. In a strain insulator, the combination with an insulating member having anangularly arranged interior shoulder, the angle of the said shoulder with reference to a plane at right angles to the normal direction of strain being not greater than forty-five degrecs, of a strain member extendin interiorly of the insulating member and including a support, and retaining means secured to the support and including a plurality of laminated plates provided with inclined or angular marginal portions extending parallel to and supported by the aforesaid shoulder and through which plates the support extends.

8. In a strain insulator, the combination with a frangible insulating member having an interiorly arranged and inclined shoulder, of a strain member extending interiorly of the insulating member and including a bolt provided with a conical head, and retaining means for said bolt, said means comprising a plate provided with an opening to receive the stem of the said holt and further provided with an inclined p0rtion adapted when said means is in assembled position to extend parallel to the said conical face of the said bolt head. 4

4. In -a strain insulator, the combination with a rangible insulatin member having an interiorly arranged and lnclined shoulder, of a strain member extending interiorly of the insulating member and including a support, and retaining means secured to the support and consisting of a plurality of laminated plates provlded with expanded inclined or angular portions extending parallel to yand `supported by the aforesaid shoulder.

5. The combination with a rangible insulating member having a recess provided with an interior inclined shoulder, of a strain member'extending interiorly of the insulating member and including a support havin a head provided with an inclined shoul er, said head being of smaller diameter than the mean diameter of the recess, and retainingmeans secured to the support and embodying a washer beneath the head having a marginal portion expanded by engage'- ment with the shoulder on the head to lock with the shoulder on the insulator member.

WALTER T. GODDARD.

Witnesses:

J. N. SAUNnnns, EDWARD A Fomszr 

